A few examples of modulated optical sources are disclosed in:                U.S. Pub. No. 2002/0097941 entitled “Asymmetric waveguide electroabsorption-modulated laser” published Jul. 25, 2002 in the names of Forrest et al;        U.S. Pub. No. 2002/0131466 entitled “Electroabsorption modulated laser” published Sep. 19, 2002 in the names of Salvatore et al;        U.S. Pub. No. 2005/0018732 entitled “Uncooled and high temperature long reach transmitters, and high power short reach transmitters” published Jan. 27, 2005 in the names of Bond et al;        U.S. Pub. No. 2007/0116398 entitled “High speed and low loss GeSi/Si electroabsorption light modulator and method of fabrication using selective growth” published May 24, 2007 in the names of Pan et al;        U.S. Pat. No. 9,438,007 entitled “Optical modulator” issued Sep. 6, 2016 to Blauvelt et al;        U.S. Pat. No. 9,564,734 entitled “Method of fabricating and operating an optical modulator” issued Feb. 7, 2017 to Blauvelt et al; and        U.S. Pat. No. 9,564,733 entitled “Method of fabricating and operating an optical modulator” issued Feb. 7, 2017 to Blauvelt et al.        
Each of the patents and publications listed above is incorporated by reference as if fully set forth herein.